Quantitative Net Water Uptake as a Predictor of Functional Outcomes After Intravenous Thrombolysis in Acute Ischemic Stroke International Multicenter Observational Retrospective Study

While the effectiveness of intravenous thrombolysis (IVT) decreases over time, patients show considerable variability in how quickly their ischemic core progresses. Quantitative net water uptake (NWU) has emerged as a biomarker indicating blood-brain barrier disruption and may better reflect the "tissue clock" than time alone. Low NWU is associated with favorable outcomes, whereas high NWU predicts poor outcomes and futile recanalization. The study aims to determine whether NWU measured on initial non-contrast CT is a treatment effect modifier for the IVT therapy.

Inclusion Criteria: * Acute ischemic stroke treated with intravenous thrombolysis * Imaging with non-contrast cranial CT on admission * Follow-up imaging with non-contrast cranial CT or MRI 12-24 hours after IVT * Final Infarct volume \> 5ml * ASPECTS available Exclusion Criteria: * Known use of oral anticoagulation (OAC) on admission * Preexisting ischemic infarction on admission non-contrast cranial CT * Patients with large vessel occlusion AIS who underwent mechanical thrombectomy * Low imaging quality precluding radiological measurements * Severe white matter lesions precluding radiological measurements * No ASPECTS